1. Field of the Invention
This invention relates to a wheel seal.
2. Description of the Related Art
With reference to FIGS. 1 and 2, partially enlarged sectional views of a bearing located in a conventional wheel hub, and of a conventional seal, the wheel hub 100 is mainly provided with an hub bore 101 through which an shaft 200. Further, a tapered roller bearing 300 is set on the shaft 200 and contained in the hub bore 101. Then, lubricant is filled into the hub bore 101 to lubricate and protect the shaft 200 and the tapered roller bearing 300, and opposite to the tapered roller bearing 300, a seal 400 is provided at the other end of the hub bore 101 to prevent the lubricant from leaking The seal 400 is an inner annular member 401. At a side of the inner annular member 401, a container space concave inwards is formed to contain one end of an annular external sleeve oil sleeve 402. A gap is kept between the inner annular member 401 and the external sleeve oil 402, and a flexible seal member 403 is provided. Two ends of the barrier 403 separately tight fit to the inner annular member 401 and the external sleeve oil sleeve 402. Thus, the outer annular member 402 of seal 400 is made to run with the wheel hub 100, which thereby prevents the seal 400 from being worn out, due to friction, and then oil from leaking
However, the gap is kept between the inner annular member 401 and outer annular member 402 of the seal 400, so foreign matters are made to easily fall into the seal 400 through the gap, which makes the barrier 403 wear down and then the lubricant leak, and even the foreign matters are made to fall into the hub bore 101, which seriously damages the shaft 200 and the tapered roller bearing 300. Further, the seal tightly fits to the hub bore, so a tool must be used to knock on the inner annular member at the time of installation for installation of the seal on the hub bore. However, due to the clearance impact, the strength is hard to transfer from the inner annular member to the outer annular member, and thus higher hammer strength is required, which easily damages the seal; it is apparent that improvement is necessarily made.
Consequently, because of the technical defects of described above, the applicant keeps on carving unflaggingly through wholehearted experience and research to develop the present invention, which can effectively improve the defects described above.